1. Getting Started

1.a. Getting started

Note:
This document assumes that you have correctly configured your kernel, its
modules for your hardware and you know the interface name of your hardware.
We also assume that you are configuring eth0, but it could also be
eno0, ens1, wlan0, enp1s0 etc.

To get started configuring your network card, you need to tell the Gentoo RC
system about it. This is done by creating a symbolic link from
net.lo to net.eth0 (or whatever the network interface
name is on your system) in /etc/init.d.

Code Listing 1.1: Symlinking net.eth0 to net.lo

# cd /etc/init.d
# ln -s net.lo net.eth0

Gentoo's RC system now knows about that interface. It also needs to know how
to configure the new interface. All the network interfaces are configured in
/etc/conf.d/net. Below is a sample configuration for DHCP and
static addresses.

Note:
If you do not specify a configuration for your interface then DHCP is assumed.

Note:
CIDR stands for Classless InterDomain Routing. Originally, IPv4 addresses were
classified as A, B, or C. The early classification system did not envision the
massive popularity of the Internet, and is in danger of running out of new
unique addresses. CIDR is an addressing scheme that allows one IP address to
designate many IP addresses. A CIDR IP address looks like a normal IP address
except that it ends with a slash followed by a number; for example,
192.168.0.0/16. CIDR is described in RFC 1519.

Now that we have configured our interface, we can start and stop it using the
following commands:

Code Listing 1.3: Starting and stopping network scripts

# /etc/init.d/net.eth0 start
# /etc/init.d/net.eth0 stop

Important:
When troubleshooting networking, take a look at /var/log/rc.log.
Unless you have rc_logger="NO" set in /etc/rc.conf, you
will find information on the boot activity stored in that log file.

Now that you have successfully started and stopped your network interface, you
may wish to get it to start when Gentoo boots. Here's how to do this. The last
"rc" command instructs Gentoo to start any scripts in the current runlevel
that have not yet been started.

Code Listing 1.4: Configuring a network interface to load at boot time